1. Field of the Invention
The present invention relates to valves, and more particularly valves for use with fluid and gaseous materials.
2. Description of Prior Art
Most valves known in the art are such that the control organs include a turnable valve stem which from the outside of the valve passes through a channel in the housing to the closure member. The channel with the stem are sealed by gaskets, and in some cases by a bellows. An important drawback of such valves is that they do not indicate any failure of the control mechanism by self-locking the valve. Another drawback is that the closure members are inside the housing, and thus difficult to get at. Furthermore, the packings around the turnable stem can constitute an area of failure which may become dangerous in conjunction with high-pressure systems and aggressive materials. It is the aim of this invention to disclose a valve which does not have the indicated weaknesses, and which offers considerable advantages, i.e. that it may be manufactured both in relatively simple and inexpensive designs for simple duties, and in more complicated designs for increased safety, that it may be controlled from a distance, that it may function as a sample-extracting-cock or as a control or gate valve.